The Low Lying Electronic States of SiO

Abstract

Perturbations in the A 1Π state of the isotopic 28Si16O and 28Si18O molecules are analyzed. The perturbing states, d 3Δ r , e 3Σ-, C 1Σ-, and D 1Δ, are identified and vibrationally assigned. Two independent methods of vibrationally numbering the perturbers, employing isotope shifts and vibrational variation of perturbation matrix elements, respectively, are described in detail and shown to be in complete agreement. Molecular constants for the eight lowest energy electronic states of SiO are presented. Semiempirical and isovalent relationships between spin-orbit and spin-spin constants are discussed.

The low-lying electronic states of SiO

“…Park and Arnold [6] deduced an jR e j 2 curve from their experiments that was very similar to that reported by Langhoff and Arnold [8] (and hence also similar to our values); this would appear to support the computed results and hence the longer lifetime. It is possible that there is no real disagreement on the emission, but rather the lifetime measured by Smith and Liszt is reduced by curve crossing to one of the four known [2] perturbing states, which is not accounted for in our calculations. Given the difference between theory and experiment, a new experimental study of SiO A state lifetime would seem ideal.…”

“…There have been numerous studies of SiO, both experimental [1][2][3][4][5][6] and theoretical [7][8][9][10]. While much is know about SiO emission, the lifetime of the A 1 P state is still in question.…”

The Electronic Spectrum of Germanium Monosulfide: Rotational Structure in the A1Π–X1Σ+ Transition in 70GeS

“…The rest of the electronic states are not involved in any direct transitions. In the isovalent molecules SiO, SiS, SiSe, SiTe, and GeO studied previously, the A 1 state was known to be extensively perturbed and in favorable cases the perturbing states could be characterized and accounted for by the remaining electronic states arising from configuration II (12)(13)(14)(15)(16)(17). Therefore, it was natural to expect the situation in GeS to be similar.…”

“…(9) revealed no perturbations in the A 1 state. But in the isovalent molecules SiO, SiS, SiSe, SiTe, and GeO (12)(13)(14)(15)(16)(17), the A 1 state is known to be perturbed to various degrees by a host of singlet and triplet states arising mainly from the . .…”

High-resolution Fourier transform emission spectroscopy of the A1Π–X1Σ+ system of 74Ge80Se

“…The 1 P state resulting from the first configuration is identifiable with the A 1 P being studied in this paper. In the isovalent molecules SiO, SiS, SiSe, SiTe, GeO and GeS studied previously, the A 1 P state was known to be extensively perturbed and in favorable cases the perturbing states could be characterized and accounted for by the remaining electronic states arising from the second configuration mentioned above [16][17][18][19][20]. Therefore, it is natural to expect the situation in GeSe, to be similar, which was another motivation for us to take up the present extensive investigations using enriched isotopes of germanium and selenium.…”